Year Percent 1950 8.19083 1955 7.59076 1960 7.00831 1965 6.97141 1970 6.97923 1975 7.00196 1980 7.07412 1985 7.41665 1990 8.05371 1995 8.18985 2000 8.59207 2005 7.43105 2010 8.37523 2015 11.20272 2020 13.526 2025 16.0607 2030 18.30682 2035 20.46766 2040 22.23253 2045 23.86137 2050 24.84395 2055 25.24707 2060 24.79853 2065 24.35231 2070 25.07255 2075 27.10549 2080 28.80663 2085 29.8757 2090 30.64465 2095 31.46264 2100 32.39391